/*
 * Copyright (c) MuleSoft, Inc.  All rights reserved.  http://www.mulesoft.com
 * The software in this package is published under the terms of the CPAL v1.0
 * license, a copy of which has been included with this distribution in the
 * LICENSE.txt file.
 */
package org.mule.util;

import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.Iterator;
import java.util.Map;

// @ThreadSafe
public class MapUtils extends org.apache.commons.collections.MapUtils
{
    /**
     * Convenience method for CollectionUtil#mapWithKeysAndValues(Class, Iterator,
     * Iterator); keys and values can be null or empty.
     */
    public static <K, V> Map<K, V> mapWithKeysAndValues(Class<? extends Map> mapClass,
                                                        K[] keys,
                                                        V[] values)
    {
        Collection<K> keyCollection = (keys != null ? Arrays.asList(keys) : Collections.EMPTY_LIST);
        Collection<V> valuesCollection = (values != null ? Arrays.asList(values) : Collections.EMPTY_LIST);
        return mapWithKeysAndValues(mapClass, keyCollection.iterator(), valuesCollection.iterator());
    }

    /**
     * Convenience method for CollectionUtil#mapWithKeysAndValues(Class, Iterator,
     * Iterator); keys and values can be null or empty.
     */
    public static <K, V> Map<K, V> mapWithKeysAndValues(Class<? extends Map> mapClass,
                                                        Collection<K> keys,
                                                        Collection<V> values)
    {
        keys = (keys != null ? keys : Collections.EMPTY_LIST);
        values = (values != null ? values : Collections.EMPTY_LIST);
        return mapWithKeysAndValues(mapClass, keys.iterator(), values.iterator());
    }

    /**
     * Create & populate a Map of arbitrary class. Populating stops when either the
     * keys or values iterator is null or exhausted.
     *
     * @param mapClass the Class of the Map to instantiate
     * @param keys iterator for Objects ued as keys
     * @param values iterator for Objects used as values
     * @return the instantiated Map
     */
    public static <K, V> Map<K, V> mapWithKeysAndValues(Class<? extends Map> mapClass,
                                                        Iterator<K> keys,
                                                        Iterator<V> values)
    {
        Map<K, V> m = null;

        if (mapClass == null)
        {
            throw new IllegalArgumentException("Map class must not be null!");
        }

        try
        {
            m = mapClass.newInstance();
        }
        catch (Exception ex)
        {
            throw new RuntimeException(ex);
        }

        if (keys != null && values != null)
        {
            while (keys.hasNext() && values.hasNext())
            {
                m.put(keys.next(), values.next());
            }
        }

        return m;
    }

    /**
     * Creates a String representation of the given Map, with optional newlines
     * between elements.
     *
     * @param props the map to format
     * @param newline indicates whether elements are to be split across lines
     * @return the formatted String
     */
    public static String toString(Map props, boolean newline)
    {
        if (props == null || props.isEmpty())
        {
            return "{}";
        }

        StringBuilder buf = new StringBuilder(props.size() * 32);
        buf.append('{');

        if (newline)
        {
            buf.append(SystemUtils.LINE_SEPARATOR);
        }

        Object[] entries = props.entrySet().toArray();
        int i;

        for (i = 0; i < entries.length - 1; i++)
        {
            Map.Entry<?, ?> property = (Map.Entry<?, ?>) entries[i];
            buf.append(property.getKey());
            buf.append('=');
            buf.append(PropertiesUtils.maskedPropertyValue(property));

            if (newline)
            {
                buf.append(SystemUtils.LINE_SEPARATOR);
            }
            else
            {
                buf.append(',').append(' ');
            }
        }

        // don't forget the last one
        Map.Entry<?, ?> lastProperty = (Map.Entry<?, ?>) entries[i];
        buf.append(lastProperty.getKey().toString());
        buf.append('=');
        buf.append(PropertiesUtils.maskedPropertyValue(lastProperty));

        if (newline)
        {
            buf.append(SystemUtils.LINE_SEPARATOR);
        }

        buf.append('}');
        return buf.toString();
    }
}
